This section is intended to introduce various aspects of the art, which may be associated with exemplary embodiments of the present disclosure. This discussion is believed to assist in providing a framework to facilitate a better understanding of particular aspects of the disclosed methodologies and techniques. Accordingly, it should be understood that this section should be read in this light, and not necessarily as admissions of prior art.
Hydrocarbon reserves are becoming increasingly difficult to locate and access, as the demand for energy grows globally. Typically, various technologies are utilized to collect measurement data and then to model the location of potential hydrocarbon accumulations. The modeling may include factors, such as (1) the generation and expulsion of liquid and/or gaseous hydrocarbons from a source rock, (2) migration of hydrocarbons to an accumulation in a reservoir rock, (3) a trap and a seal to prevent significant leakage of hydrocarbons from the reservoir. The collection of these data may be beneficial in modeling potential locations for subsurface hydrocarbon accumulations.
At present, reflection seismic is the dominant technology for the identification of hydrocarbon accumulations. This technique has been successful in identifying structures that may host hydrocarbon accumulations, and may also be utilized to image the hydrocarbon fluids within subsurface accumulations as direct hydrocarbon indicators (DHIs). However, this technology may lack the required fidelity to provide accurate assessments of the presence and volume of subsurface hydrocarbon accumulations due to poor imaging of the subsurface, particularly with increasing depth where acoustic impedance contrasts that cause DHIs are greatly diminished or absent. Additionally, it is difficult to differentiate the presence and types of hydrocarbons from other fluids in the subsurface by such remote measurements.
Current geophysical, non-seismic hydrocarbon detection technologies, such as potential fields methods like gravity or magnetics or the like, provide coarse geologic subsurface controls by sensing different physical properties of rocks, but lack the fidelity to identify hydrocarbon accumulations. These tools may provide guidance on where in a basin seismic surveys should be conducted, but do not significantly improve the ability to confirm the presence of hydrocarbon seeps or subsurface hydrocarbon accumulations. Other non-seismic hydrocarbon detection technologies may include geological extrapolations of structural or stratigraphic trends that lead to prospective hydrocarbon accumulations, but cannot directly detect these hydrocarbon accumulations. Other techniques may include monitoring hydrocarbon seep locations as an indicator of subsurface hydrocarbon accumulations. However, these techniques are limited as well. For example, ssatellite and airborne imaging of sea surface slicks, and shipborne multibeam imaging followed by targeted drop core sampling, have been the principal exploration tools used to locate potential seafloor seeps of hydrocarbons as indicators of a working hydrocarbon system in exploration areas. While quite valuable, these technologies have limitations in fidelity, specificity, coverage, and cost.
As a result, an enhancement to exploration techniques that integrates various other techniques is needed. This integration of techniques may provide a pre-drill technology that determines the presence and location of thermogenic hydrocarbon seepages from the seafloor. Further, this method may be utilized to locate seafloor hydrocarbon seeps accurately and cost-effectively over the basin-to-play scale as a means to enhance basin assessment and to high-grade areas for exploration.